Ratifying Crimea vote will be 'back-door annexation'

US Secretary of State John Kerry has warned Russia that ratifying a Crimea referendum result in the Russian parliament will amount to a "back-door annexation" of the Ukrainian region.

John Kerry said the US respects Russia's interests in the Crimea region but cannot endorse an "illegal" referendum.

Mr Kerry said the international calls for sanctions as "a response" to the "illegal" referendum being held were not a threat to Russia but a necessary step to "respecting the integrity of Ukraine".

"It is not our preference," he said, but a "justified" step due to the "breach of international law".

He added, though, that the international community still "does not know definitively" what Vladimir Putin will decide about Russia's response to a referendum on Crimea and insisted the US had put "plenty of options on the table" for the Russian President to take a different course.